The Global Positioning System: Assessing National Policies

By Scott Pace; Gerald Frost et al. | Go to book overview

Chapter One
INTRODUCTION

The Global Positioning System (GPS) is a U.S. military space system operated by the U.S. Air Force. It consists of three segments: The space segment of GPS is a constellation of 24 satellites that broadcast precise time signals. When the satellites are in view of a suitable GPS receiver, these signals can be used to aid position-location, navigation, and precision timing. The control segment consists of a control center and access to overseas command stations, and the user segment includes GPS receivers and associated equipment. The GPS space and ground segments were developed over two decades at the cost of more than $10 billion.1 The purpose of this massive effort was to provide a highly accurate, secure, reliable way for U.S. forces to navigate anywhere in the world, without having to reveal themselves through radio transmissions.

GPS satellites transmit two different signals: the Precision or P-code and the Coarse Acquisition or C/A-code. The P-code is designed for authorized military users and provides what is called the Precise Positioning Service (PPS). To ensure that unauthorized users do not acquire the P-code, the United States can implement an encryption segment on the P-code called anti-spoofing (AS). The C/A-code is designed for use by nonmilitary users and provides what is called the Standard Positioning Service (SPS). The C/A-code is less accurate and easier to jam than the P-code. It is also easier to acquire, so military receivers first track the C/A-code and then transfer to the P-code. The U.S. military can degrade the accuracy of the C/A-code by implementing a technique called selective availability (SA). SA thus controls the level of accuracy available to all users of the Standard Positioning Service.

GPS had its wartime debut during the Persian Gulf War and was one of the most prominent military technologies of the war. Although the entire constellation of satellites was not yet complete, GPS signals were available for many hours a

____________________
1
Senator James Exon, "GPS's Limitless Potential", April 30, 1993 speech on the floor of the U.S. Senate, reprinted in Space News, May 31-June 6,1993, p. 15. The ground segment consists of the master control station and worldwide monitoring stations.

-1-

Notes for this page

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this book

This book has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this book

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this page

Cited page

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited page

Bookmark this page
The Global Positioning System: Assessing National Policies
Table of contents

Table of contents

  • Title Page i
  • Preface iii
  • Contents v
  • Figures ix
  • Tables xiii
  • Summary xv
  • Acknowledgments xxix
  • Acronyms xxxi
  • Chapter One - Introduction 1
  • Chapter Two - National Interests and Stakeholders in Gps Policy 11
  • Chapter Three - National Security Assessment 45
  • Chapter Four - Commercial Assessment 93
  • Chapter Five - Institutional and Legal Assessment 163
  • Chapter Six - Conclusions and Recommendations 195
  • Appendix A - Gps Technologies and Alternatives 217
  • Appendix B - Gps History, Chronology, and Budgets 237
  • Appendix C - Gps Policy References 271
  • Appendix D - International Legal References for Gps 293
  • Bibliography 305
  • Gps Interviews 361
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this book

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
/ 368

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

    Already a member? Log in now.